ML19106A144
| ML19106A144 | |
| Person / Time | |
|---|---|
| Issue date: | 04/16/2019 |
| From: | Office of Nuclear Security and Incident Response |
| To: | |
| Shared Package | |
| ML19106A141 | List: |
| References | |
| Download: ML19106A144 (44) | |
Text
Part 2: Emergency Preparedness Philosophies
Topics:
- Defense-in-Depth (DiD)
- Protective Action Guidelines (PAGs)
- Emergency Planning Zones (EPZs)
- Onsite/Offsite Emergency Response Facilities (ERFs)
- Emergency Classification Levels (ECLs)
- Emergency Action Levels (EALs) 2
Defense-in-Depth Safety Philosophy Level 1 Prevention of abnormal operation and failures by requiring conservative design and high quality in construction and operation Level 2 Control of abnormal operation and detection of failures by requiring controlling, limiting and protection systems and other surveillance features.
Level 3 Control of accidents within the design basis by requiring engineered safety features and accident procedures.
Level 4 Control of severe plant conditions, including prevention of accident progression and mitigation of the consequences of severe accidents by requiring complementary measures and accident management.
Level 5 Mitigation of radiological consequences of significant releases of radioactive materials by requiring emergency planning, preparation, and response.
The underlying philosophies of conservatism, quality assurance, and safety culture add to defense-in-depths five independent levels.
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Defense-in-Depth Safety Philosophy The NRC Glossary defines defense-in-depth as:
- An approach to designing and operating nuclear facilities that prevents and mitigates accidents that release radiation or hazardous materials.
- The key is creating multiple independent and redundant layers of defense to compensate for potential human and mechanical failures so that no single layer, no matter how robust, is exclusively relied upon.
- Defense-in-depth includes the use of access controls, physical barriers, redundant and diverse key safety functions, and emergency response measures.
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5 High quality design and construction Design for maximum safety in normal operations Provide protective safety system to minimize damage, assuming upsets will occur Redundant and diverse safety systems Containment structures Emergency planning Defense-in-Depth
Emergency Planning
- Reduce complex decision-making
- Simplify choice of possible responses
- removes non-viable alternatives from consideration during the response
- Allow for:
- Consistent and practices approaches
- Addressing a spectrum of challenges irrespective of causes 6
LO 12
Protective Action Guides Protective Action Guide (PAG) is the projected dose from unplanned release at which a specific protective action to reduce or avoid dose is recommended
- Used as guidance for triggering appropriate protective actions to minimize dose
- Balances the benefit of dose reduction against the risks of implementing the action
- At PAG levels, no health effects detectable, even for sensitive populations, such as pregnant women 7
- Used as a decision aid
- Protective action recommendations
- Protective action decisions
- Within the context of other factors of emergency
- Represent trigger levels
- Not meant for
- Strict numerical criteria
- Establishing acceptable level of risk
- Establishing safe or unsafe conditions
- Establishing regulations or standards
- Superseding environmental laws 8
- Based on projected dose in early phase
- does not count dose received
- Early phase protective actions
- Evacuation / sheltering when 1-5 rem (10-50 mSv) whole body dose is projected during first 4 days.
- Potassium Iodide KI administration
- 25 rem (250 mSv) dose to thyroid is projected
- PAG levels are so low that no ill health effects detectable
- PAGs are not bright lines and circumstances may warrant a lower or higher action level 9
LO 13
Emergency Planning Zones (EPZs)
- areas for which planning is recommended to assure that prompt and effective actions can be taken to protect the public in the event of an accident.
- Plume Exposure Pathway
- 10 mile radius
- Ingestion Exposure Pathway
- 50 mile radius 10 LO 12
Emergency Planning Zones (EPZs)
- Plume Exposure Pathway
- Boundaries determined by topography, political jurisdictions
- Roads, rivers, lakes, peninsulas
- Municipal, County, State jurisdictions 11 LO 12
Emergency Planning Zones (EPZs)
- Plume Exposure Pathway
- Provisions for action within EPZ
- Prompt decision-making for public protective actions
- Development of evacuation plans
- Public information program
- Prompt public alerting and notification
- 24/7 communication capability with State/local officials
- Monitoring of offsite radiological release
- Maintaining Emergency Operations Centers
10-mile radius EPZ may be divided into subzones defined by geopolitical boundaries or topography that are easily recognizable to the public Note that the EPZ can be slightly larger or smaller than 10-miles to take advantage of recognizable geopolitical boundaries
Alert and Notification System
- Capability to promptly alert the public within the Plume Exposure Pathway EPZ of an emergency
- Informs the public of protective actions
- Functions:
- Warning signal to seek additional information
- Provide instructions 14 LO 8
Prompt Public Notification
- Alert and Notification Systems (ANS)
- Sirens
- REVERSE 911
- Route alerting
- Emergency Alert System (EAS)
- Highway message boards
- Integrated Public Alert and Warning System (IPAWS) 15
Public Information -- Calendars 16
Public Information
Modern Public Information -- Apps 18
- Protect from consumption of contaminated food
- Considerable time to act (typically State level)
Ingestion Exposure Pathway EPZ
- Approximately 50 miles in radius
- Size based upon:
- Contamination will not exceed PAGs beyond 50 miles
- Particulate material would be deposited within 50 miles
- Likelihood of exceeding ingestion PAGs at 50 miles is comparable to exceeding plume exposure PAGs at 10 miles
Offsite Onsite
Offsite
- FEMAs Responsibilities
- Assisting States
- Review State and Local plans
- State and Local Responsibilities
- Plan
- Maintain preparedness
- Implementing protective actions
- Alerting
- Sheltering
- Evacuating 21 LO 13
Onsite
- Licensees Responsibilities
- Maintaining DiD
- Implementing actions
- Prevent,
- Reverse, and
- Stop the emergency
- Classification
- Notification
- Making protective action recommendations
- NRCs Responsibilities
- Monitor the licensee and emergency
- Provide technical support to
- Licensee
- Other Federal Agencies
- States and locals if requested 22 LO 10, 11, 12, & 14
Onsite EP
- Emergency Planning Professional Staff
- Every NPP site has EP department
- Maintains licensees emergency plan
- Develops and coordinates drills and exercises
- Coordinates with offsite authorities and organizations
- Coordinates with onsite departments and activities
- Provides training
- Maintains preparedness equipment and facilities
- Assists in licensee response 23
Licensee Emergency Response Facilities (ERFs)*
-Control Room (CR)
-Technical Support Center (TSC)
-Operations Support Center (OSC)
-Emergency Operations Facility (EOF)
-Alternate facility(ies)
-Joint Information Center (JIC)
- actual facility names may vary from site to site
Control Room
- Normal plant operations
- Contains instrumentation, controls, and displays for:
- Nuclear Systems
- Steam Systems
- Electrical Systems
- Safety Systems
- Accident Monitoring Systems LO 6 25
Control Room
- Emergency Response Plant Operations
- Diagnose abnormal conditions
- Perform corrective actions
- Mitigate conditions
- Manage plant operations
- Restore plant to safe conditions
- Recover from abnormal conditions LO 5, 10, 11, & 14 26
Control Room as Emergency Response Facility
- Initial Emergency Response Functions
- Emergency Declarations
- Offsite Notifications
- PAR, if needed
- Augmented at Alert
- TSC reduces congestion and confusion in Control Room (CR)
- Located near CR for ready access
- Monitor, diagnose, and mitigate
- Access to technical data
- Access to plant instrumentation
- Engineering support for CR
- Onsite Radiological Monitoring
- Habitability
- Reliable power
Operations Support Center
- OSC reduces congestion and confusion in Control Room
- Emergency response craft personnel
- coordination by operations staff and TSC
- Coordination of damage control teams
- Health Physics briefings
- EOF interfaces with offsite agencies; outward focus
- Response functions
- Emergency Director
- Communications
- Public information
- Accident analysis
- Dose assessment
- Offsite monitoring
- PAR development/decisions
- State and county liaisons
- Support to TSC
- Normally outside Plume Exposure Pathway EPZ
- May be in another State or local area.
- JIC Coordinates dissemination of public information
- State/county liaisons
- Media liaisons
- Location for media briefings and news conferences Joint Information Center
Offsite Emergency Operations Centers
- Manage preparations for event and state or local response
- Provide a location for decision makers
- Provide data and information about event
- Communicate with the licensee and other support organizations
- Coordinate activities of interest at State level
- Technical assessment of event
- Radiological dose assessment
Event Classification Levels (ECLs)
- Provide a basis for a progressive response to an event
- ECLs from least to most severe are
-Notification of Unusual Event (NOUE or UE)
-Alert
-Site Area Emergency (SAE)
-General Emergency (GE) 33 LO 9
Notification of Unusual Event (NOUE)
LO 9 34
- Events are in progress or have occurred which indicate a potential degradation of the level of safety of the plant or indicate a security threat to facility protection.
- No release expected
Alert
- Events are in progress or have occurred which involve actual or potential substantial degradation of the level of safety of the plant or a security event that involves probable life threatening risk to site personnel or damage to site equipment because of malicious dedicated efforts of a hostile act.
LO 9 35
Site Area Emergency (SAE)
LO 10 36
- Events are in progress or have occurred which involve actual or likely major failures of plant functions needed for protection of the public or security events that result in intentional damage or malicious acts: (1) toward site personnel or equipment that could lead to the likely failure of, or; (2) prevents effective access to, equipment needed for the protection of the public.
General Emergency (GE)
- Events are in progress or have occurred which involve an actual or imminent substantial core degradation or melting with the potential for loss of containment integrity or security events that result in an actual loss of physical control of the facility.
Flow of Events
- Initiating Conditions
- Emergency Action Levels
- Emergency Classifications
- Offsite Actions, if necessary
Initiating Condition An event of condition that corresponds with the definition of one of the four emergency classification levels
- An IC can be expressed by:
- Measurable parameter (RCS temperature)
- Event (fire, flood, security)
- Barrier breach
- Fuel
- Containment
Emergency Action Level A predetermined, site-specific, observable threshold for an IC that, when met or exceeded, places the plant in a given emergency classification level
- EALs may utilize:
- Instrument readings or status indications
- Observable events
- Results of calculations or analyses
- Entry into particular plant procedures
- Occurrence of natural phenomena
ECL: General Emergency AGI Initiating Condition: Release of gaseous radioactivity resulting in offsite dose greater than 1000 mrem TEDE or 5000 mrem thyroid CDE Operating Mode Applicability: All Emergency Action Levels ( 1 or 2 or 3)
(1) Reading on radiation monitor HVS-RM-1001A greater than 15,000 CPM for 15 minutes or longer.
(2) Dose assessment using actual meteorology indicates doses greater than 1000 mrem TEDE or 5000 mrem thyroid CDE (3) Field survey results indicate greater than 1000 mrem/hr expected to continue for 60 minutes Basis:
Excerpt of Typical EAL Scheme
Facility Staffing vs Classification 42
Review
- List the onsite emergency response facilities
- List the offsite emergency response facilities.
- List the Alert Notification System (ANS/PANS) devices to notify the public of an emergency.
- List the four emergency classification levels for nuclear power plants from least to most severe.
- List the two forms of emergency planning zones for operating nuclear power plants.
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Summary
- We reviewed the role of
- defense-in-depth,
- protective action guides,
- emergency planning zones,
- emergency response facilities,
- emergency classification levels, and
- emergency action levels within the emergency preparedness and planning.
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